The LM3429 is a versatile high voltage N-channel MosFET controller for LED drivers. It
can be easily configured in buck, boost, buck-boost and SEPIC topologies. This flexibility, along
with an input voltage rating of 75V, makes the LM3429 ideal for illuminating LEDs in a very
diverse, large family of applications.
Adjustable high-side current sense voltage allows for tight regulation of the LED current
with the highest efficiency possible. The LM3429 uses Predictive Off-time (PRO) control, which is a
combination of peak current-mode control and a predictive off-timer. This method of control eases
the design of loop compensation while providing inherent input voltage feed-forward
compensation.
The LM3429 includes a high-voltage startup regulator that operates over a wide input
range of 4.5 V to 75 V. The internal PWM controller is designed for adjustable switching
frequencies of up to 2 MHz, thus enabling compact solutions. Additional features include analog
dimming, PWM dimming, overvoltage protection, undervoltage lock-out, cycle-by-cycle current limit,
and thermal shutdown.
